Last summer, the Ebola outbreak in West Africa was all over the news. At the outbreak’s height, many health officials feared the disease would spread across the globe, and indeed individuals in the United States and Europe were diagnosed with the disease. However, cases outside of West Africa were kept isolated and a global outbreak of the disease was prevented.

On June 11, 2009, the World Health Organization raised the alert level to phase 6meaning that the occurrence of swine flu can be categorized as a pandemic. Since the virus was first identified, over 30,000 cases of swine flu have been diagnosed in North America, Europe, Australia, South America, and other locations across the globe. The WHO opted to change the alert level due to the global spread of the flu virus, and not because of the severity of the virus. Thus far, most cases of the H1N1 flu virus in the United States have been mild, and most people infected by the virus have recovered without requiring professional medical treatment. However, because the H1N1 flu virus is a new virus, most people have little to no immunity against it. Health officials worry that the severity of the H1N1 flu virus could increase over time, especially during the fall and winter when the flu season hits. This is especially worrisome given the current lack of a vaccine against the virus.

Cases of the H1N1 flu virus were first detected in Mexico, and have since spread into the United States and worldwide. The first confirmed case of the H1N1 flu virus in the United States was identified on April 15, 2009. Since the outbreak began, cases have been identified in all 50 states. Early outbreaks around the globe centered on travelers who had recently returned from trips to Mexico. Currently, countries in the Southern Hemisphere, including Australia and New Zealand, are experiencing an rise in the number of H1N1 flu virus infections; that part of the world is just entering the influenza season.

Of the 30,000 reported cases of H1N1 flu virus infection, there have only been 144 deaths. To put this in perspective, according to data presented by the Centers for Disease Control (CDC), every year in the United States, about five to 20 percent of the population comes down with a case of the seasonal flu, and about 36,000 Americans die every year from flu-related complications.

Following are a few answers to some questions you may have about the H1N1 flu virus.

What is the H1N1 virus?

The influenza A(H1N1) virus is a new type of flu that was first detected in the United States in April 2009.

The H1N1 flu virus. (Photo credit: CDC Influenza Laboratory)

Why was it called the swine flu?

The H1N1 virus was originally referred to as the “swine flu” because initial testing showed that the virus carried a number of genes similar to flu viruses that typically occur in North American pigs. Further testing showed that the virus is actually a quadruple reassortment virus that contains two genes that normally infect European and Asian pigs along with a gene from humans and a gene from birds.

What are the symptoms of the H1N1 virus?

Symptoms of the H1N1 flu virus are similar to the symptoms of the seasonal flu. These symptoms include fever, body aches, headache, chills, cough, sore throat, and fatigue. In some cases, occurrences of diarrhea and vomiting have also been reported. Although cases in the United States have generally been mild, some populations of people may be more susceptible to the virus, including the very young the very old, pregnant women, and those with chronic conditions or compromised immune systems.

How is the virus spread?

The virus is spread by human-to-human contact through coughing, sneezing, or touching something infected by the virus and then touching one’s eyes, nose, or mouth. You cannot contract the H1N1 virus by eating cooked pork or pork products.

What are ways to prevent illness?

Wash your hands frequently with soap and water. Alcohol-based hand sanitizers can also be used to protect yourself from flu germs. Use a tissue to cover your mouth when you cough or sneeze and throw the tissue away after it’s used. If you have symptoms of the flu, stay at home. If at all possible, limit your contact with those you know to be infected with the H1N1 flu.

Is there a vaccine for the H1N1 virus?

There is not currently a vaccine for the H1N1 virus, though scientists are at work developing one. There are several antiviral medications that are recommend for use for those who have the H1N1 virus such as oseltamivir and zanamavir. These medications help prevent the flu virus from reproducing in your body and make flu symptoms milder. However, in many cases getting plenty of rest and drinking plenty of fluids is all that is necessary to get over a case of the H1N1 flu.

How long do the immune systems B memory cells remember? Recent studies focused on the 1918 H1N1 influenza virus have finally given researchers a clue. In late 2008, lab tests revealed that survivors of the 1918 influenza pandemic could still produce the specific antibodies their immune systems used to fight the 1918 flu virus. When a pathogen, such as the 1918 flu virus, enters the body, some B cells become activated to produce antibodies, while other B cells produce memory cells. B memory cells remember how to make an antibody for a particular pathogen. If the pathogen attacks again, the B memory cells produce B cells that make antibodies to fight the pathogen.

In 2005, investigators recovered preserved 1918 flu virus samples from bodies of flu victims found frozen in Alaskan soil. A team of researchers then took blood samples from 32 survivors of the 1918 flu pandemic, who are now between the ages of 91 and 101 years old. Then researchers put the virus to the test in the lab. Test results confirmed that the antibodies from blood samples of the surviving flu victims were still able to fight the 1918 flu virus! The B cells of the survivors immune systems could still secrete antibodies that bound to the 1918 antigen. These B cells, made specifically to fight the 1918 antigen during the pandemic, had waited between 60 to 90 years for a second round with the virus.

The 1918 flu pandemic is the most devastating on record, having killed nearly 50 million people worldwide. The fact that survivors of the pandemic have antibodies that can still fight the 1918 flu nearly 90 years later is a major breakthrough in immune system research. Its possible that these antibodies could be used to develop treatments for future outbreaks of flu strains similar to the 1918 virus.

The last flu pandemic ended in 1968; it was the third flu pandemic of the 20th century. Experts at the World Health Organization (WHO) believe that we are closer to another flu pandemic than any time since then. However, there is no way to predict when a pandemic will hit because each past pandemic was very different. National and multinational organizations must use other tools to anticipate and prepare for a grave public health threat.

The WHO uses a pandemic alert system to track whether a new virus strain is at risk to start a pandemic. The alert system runs from phase 1, which stands for no new virus strain infecting humans, to phase 6, describing a pandemic. Moving from one phase of alert to another is the decision of the Director-General of WHO and is influenced by the characteristics of the virus and how easily it is spread, among other things. The world is now in phase 3, characterized by the new influenza virus subtype H5N1 avian flu. Bird flu, as it is known, causes disease in humans but does not spread from human to human efficiently or sustainably.

There are different goals, actions, and policy decisions for each stage of the WHO phases. These range from preparedness, use of isolation or quarantine and vaccinations and antiviral medications to the maintenance of civil order in a pandemic period.

Another tool used by organizations is computer modeling. Currently there are computer models that simulate pandemics in the United States and other countries. The models are based on previous pandemic information and help officials when drafting preparedness plans. Researchers continue to refine their models and test scenarios as new information becomes available.

With better information and better responses, hopefully the next pandemic won’t take as many lives when it finally strikes.